nsg370 pilot bearing ./ bushing

[jeeper.sd]

the pilot bearing/ bushing outside diameter seems to b the same from the 4.0 crank to the 258. however the depth on the t he 4.0 is deeper then the 258 so when it is pressed in it sticks out a little and not flush on the 258 like on the 4.0 crank.... is this going to b a problem? do i need a diff bushing or this will not cause a problem??

[Jim K in PA]

Measure the depth from the face of the crank flange where the flywheel mounts to the end of the pilot hole bore on both cranks. As long as the exposed end of the bushing in the 258 crank is not any closer to the flange face than the end of the bore on the 4.0 crank, you should not have any interference problems. Ideally you want that bushing fully supported, but as long as only a small percentage is left exposed, it should not cause a problem.

Post up some pictures if you can. What year 4.0 crank are you coming from?

[jeeper.sd]

its a 2005 4.0 ill try to get some pics up this weekend ... and thanks for the advice,

[Jim K in PA]

You're welcome and thanks for the heads up. I just got my 258 crank today that will be going in my '05 block with NSG370 trans, so I'll be sure to check this out on my setup.

[Jpross]

What ended up being the solution to this? I will have the same configuration.

[Cheromaniac]

From my Jeep 4.0 Performance site:

'92-'99 AX15 and NVG3550:

OEM pilot bearing 53009180AB for '87-'91 engine or stroker
OEM pilot bearing 53009180AB or 53009181 for '92-'06 4.0 engine.